SunsetLint: GitHub App finds retiring AI model IDs in your repos

SunsetLint is a GitHub App that scans repositories for AI model identifiers with announced shutdown dates, reporting each match by file and line alongside the retirement date and the provider's recommended replacement. It installs with read-only access, opens one rolling issue per repository, and a Pro tier adds pull request checks that flag newly added references to retiring IDs. The first verified rule covers Claude Sonnet 4.5, which Anthropic says retires on 30 November 2026.